The present invention relates to flood control and, more particularly, to improved impoundment and diversion systems for preventing or mitigating flooding.
In many communities, the development of populated areas with consequent closely spaced housing units, large paved areas, such as the parking lots of shopping centers, numerous streets, and general lack of capability for the earth to absorb moisture has led to periodic flooding in times of heavy rainfall as well as during seasons of the year when watershed is considerable.
This problem has been further compounded in some areas because of the improper connection of roof drains to the sanitary sewer system. Therefore, when there is heavy rainfall, the runoff from roofs of buildings is added to the sometime marginal sewage drainage provided by an existing sanitary sewer system, some of which are quite antiquated and marginal at best. This has increasingly resulted in basement flooding, backing up of sewer drains and extensive damage, produced by flooding, to building substructures, foundations and basements.
Yet another problem has been the construction of residential units in areas intrinsically prone to flooding with consequent public attention being directed to the hapless residents who find themselves the victims of poor urban planning which has been compounded by an adequate storm and sanitary sewer drainage.
Such flooding, which has produced great economic loss and untold inconvenience and hardship in many parts of the country, is a product of our time. These problems are not concerned with merely one locality or even one type of drainage system, but rather effect diverse regional areas and cut across political, demographic and economic lines. Increasingly, they touch the lives, burden the pocketbooks and impose loss and hardship to persons of all class and status. Industry and business, in general, also feel the negative impact of these losses.
The efforts of man to control flooding are of ancient origin, dating back perhaps to individuals who first observed the successful work of beavers in damming streams. Thus, the use of dams across streams has been an old expedient, dating back to early civilization and used continuously ever since.
Modern communities in which there is substantial periodic flooding with loss of the foregoing character frequently visited upon the population are mute testimony to the fact that mankind has failed to cope always with the vicissitudes of nature and, as a consequence, society finds itself beset with the problem of flooding.
Analysis of the patents of prior efforts of others to solve these problems reveals the inadequacy of prior approaches. Thus, Butz U.S. Pat. No. 1,032,186 provides an early disclosure of a reservoir collection system in which water can drain into a reservoir to permit handling of a large quantity of the water when there is runoff of the same. This patentee contemplated that the water would be stored for later use, e.g., availability in dry weather.
Alsberg et al U.S. Pat. No. 3,837,168 discloses a drainage system for reducing flooding, the inventors having contemplated the recharging of underground water supplies through what amount to so-called connectors in the nature of wells. These permit the runoff water temporarily collected in storage channels to be routed into aquifers or other underground water sources, but this is inappropriate for most parts of the country and totally unsuitable where the need is to control flooding from sewers.
Stevenson U.S. Pat. No. 3,625,011 reveals a drainage system for artificial playing surfaces, which, of course, do not absorb water like conventional turf playing surfaces. Furman U.S. Pat. No. 4,247,220 may simply be noted as revealing that it has been known to utilize an underground reservoir for fluids, albeit liquid fuels.
None of these efforts of the prior art have produced a suitable answer to the needs presented by flooding problems of the type which are discussed above. These prior developments are not adequate for providing relief from the flooding which occurs because of the inadequacy of existing drainage facilities, whether such is a stream, canal, creek, culvert, sanitary sewer, storm sewer, or other conventional means for providing normal drainage of sewage or surface water.
It is an object of the present invention to provide impoundment and diversion systems for preventing or at least mitigating flooding which otherwise results from inadequate conventional drainage, and especially suitable for reducing the occurrence of local flooding along drainage facilities especially in areas where occasional conditions overtax existing drainage facilities.
It is a further object of the invention to provide such systems which provide temporary water storage to achieve effective flood relief in conjunction with various existing types of drainage facilities including streams, canals, creeks, culverts, sanitary sewers, storm sewers and various other conventional means for providing normal drainage of sewage or surface water.
It is also an object of the invention to provide such systems which permit existing drainage facilities to handle greater than normal surface water or sewage runoff as may occur due to heavy rainfall or may result from seasonal conditions resulting in heavy watershed and the like.
It is an object of the invention to provide such impoundment and diversion systems which can be utilized effectively in built-up and populated areas and which can provide effective relief from basement flooding and backing up of drains.
It is an object of the invention to provide such systems which can avoid the extensive damage, losses and difficulties which have resulted from flooding in relatively heavily populated urban areas when existing drainage facilities are inadequate to handle storm and sanitary sewer drainage which may result in occasional flooding.
A further object of the invention is to provide such impoundment and diversion systems which can be used in conjunction with existing drainage facilities without destroying the capability of using areas adjacent these existing drainage facilities for other purposes, and thereby maintaining the character and utility of such adjacent areas and avoiding disruption and dedication of otherwise useful areas.
It is also an object of the present invention to provide such impoundment and diversion systems which can be relatively economical, easily developed and constructed in various existing problem areas in many communities and which can be tailored to accommodate peculiar or unusual geographical or geological constraints often encountered in these areas.
Briefly, the invention contemplates various embodiments of a system for preventing or mitigating flooding. The system is used in conjunction with an existing drainage facility such as a creek, sewer or the like. More specifically, such a system comprises a reservoir, which may either be an excavation or, more preferably, a subterranean chamber, located proximate to the drainage facility. The reservoir is intended to impound water from the drainage facility. Diversion means is employed for diverting water to the reservoir for temporary storage therein in response to abnormal volumetric water flow in the drainage facility, and for returning the temporarily stored water to the drainage facility upon return to normal volumetric flow therein. The diversion means may include various conduits between the reservoir and the drainage facility and, in the case of a creek, also includes a wall constructed across the creek to limit the flow therein.
Other objects will be in part apparent and in part pointed out hereinbelow.